Self-employed truck drivers who own their own equipment and contract with trucking companies and shippers to move freight are a dying breed and can't be counted on as an additional source of truckload capacity if the economy picks up steam and large fleets are too busy to take on extra business, analysts say. Owner-operators aren't going away, but the non-employee driver segment has undergone tremendous change since 2000 in the face of sharply higher operator costs and scrutiny by safety regulators. A new 18-wheeler today costs more than $125,000, a 30 percent price increase from older models, in part because of requirements for clean-burning diesel engines. Truck operators also are under pressure from high fuel ...